Catch cord lockstitch selvage method and mechanism for producing same



United States Patent Inventor Wilfred Francis DesRosiers Paxton, Mass.

Appl. No. 801,223

Filed Jan. 28,1969

Patented Dec. 29, 1970 Assignee Crompton & Knowles Corporation Worcester, Mass.

a corporation of Massachusetts Continuation of application Ser. No. 650,304, June 30, 1967, now abandoned. This application Jan. 28, 1969, Ser. No. 801,223

CATCH CORD LOCKSTITCH SELVAGE METHOD AND MECHANISM FOR PRODUCING SAME 22 Claims, 19 Drawing Figs.

US. Cl 139/124, 139/118,139/383,139/385 Int. Cl 003d 47/46, D03d 5/00 Field of Search 1 39/1241,

[5 6] References Cited UNITED STATES PATIENTS 1,296,025 3/1919 Waite 139/124 1,604,365 10/1926 Mutzberg 1 139/124 1,702,289 2/1929 Zimmerer, Jr... l39/385X 2,471,758 5/1949 Libby 139/124 2,584,891 2/1952 Libby 139/383 2,758,614 8/1956 Silberman et al. 139/124 3064.689 1 1/1962 Piazzolla et a1. 139/124 3,403,706 10/1968 Shackleton,.lr. et al 139/124 3,411,549 11/1968 Muller 139/124 Primary Examiner-James Kee Chi Attorney-l-loward G. Garner, Jrl

ABSTRACT: A knitted lockstitch selvage for a needle loom fabric formed from two or more catch cords which alternate in a predetermined sequence. The catch cords are mechanically controlled so that they will be separately picked up by the knitting needle which will draw loops thereof, through the weft loops according to a predetermined sequence. The invention includes mechanism for carrying out this method.

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INVENTOR WILFRED F. Des ROSIERS I CATCH CORD LOCKSTITCII SELVAGE METHOD AND MECHANISM FOR PRODUCING SAME This application is a continuation of my earlier application, Ser. No. 650,304, filed June 30, 1967, entitled Catch Cord Lockstitch Selvage Method, and Mechanism to Produce Same, now abandoned.

The present application is related to a pending application owned by the assignee and identified as follows: John D. Shackleton and Clarence R. Kronoff Narrow Fabric Loom;" Ser. No. 58l,2l2;,filed Sept. 22, 1966, now U.S. Pat. No. 3,403,706. The catch cords are formed into knitting loops through the weft loops in the same manner as shown in FIGS. 7-10 of the above application with the exception that in the present application two or more catch cords are used instead of one.

This invention relates to apparatus and methods for manufacturing woven fabrics wherein the weft is inserted into successive warp sheds in loop or hairpin form, and the fabrics produced thereby.

More particularly, the invention is concerned with the formation of ravelproof selvages for suchfabrics wherein the loop of weft in one shed is bound or held together with the weft loops of adjacent sheds. f

In the past, weft loops in such fabrics have been bound together by several different methods with varying degrees of success. In one of these methods the loops of weft project from the edge of the fabric and are pulled through preceding loops to interknit the wefts. However, this method has two main deficiencies in that these loops form an objectionable thick bead-like edge and will still ravel in one direction. U.S. Pat. No. 3,102,557 illustrates this method.

Another method has used a catch cord which is guided into contact with a reciprocating knitting needle at the edge of the fabric. This needle penetrates the weft loops and pulls or draws a loop of the catch cord through the weft loop. The pulled loop is held by the shank of the needle when it enters a successive weft loop. The needle then pulls a second loop from the catch cord through the successive weft loop and the first catch cord loop, which is now cast off the needle. This continues and forms a knitted chain from the catch cord, the loops of which bind the weft loops together. This method avoids the objectionable bead noted above but does not produce a ravelproof selvage. U.S. Pat. Nos. 1,296,025 and 1,604,365 illustrate this method.

A third method has been used to produce a ravelproof fabric which combines the two methods noted above. In this method both the catch cord and the weft loops are laid into the hook of the needle and interknit. This produces a ravelproof fabric, but also produces an even larger bead than did the first method. U.S. Pat. No. 2,800,927 illustrates this method.

The present invention avoids the above objections and has therefore as one of its principal objects, a fabric having a lockstitch selvage in which the loops of weft are held together by a knitted ravelproof chain of catch cord yarns.

Another object of the invention is the provision of an elastic fabric with a ravelproof catch cord selvage and a decorative fringe.

A further object of the invention is to provide means for producing a ravelproof catch cord selvage.

A still further object of the invention is to provide a method of producing a ravelproof catch cord selvage.

Other objects and the details of that which is believed to be novel will be clear from the following descriptions and claims taken with the accompanying drawing which illustrates the invention and in which:

FIG. I is a fragmentary plan view ofa needle loom embodying the invention and showing the knitting needle in position to pick up one of the catch cords;

FIG. 2 is a fragmentary plan view illustrating a further step of pulling the catch cord througha previous knitting loop;

FIG. 3 is a fragmentary plan view similar to FIG. 1 illustrating the knitting needle in position to pick up a different catch cord from that shown in FIG. 1;

FIG. 4 is a view also similar to FIG. 2 but showing the second catch cord picked up in FIG. 3 being pulled through the loop formed of the catch cord picked up in FIG. 2;

FIG. 5 is a diagrammatic view of a type of an elastic fabric which may be produced according to the present invention and shown in its stretched condition;

FIG. 6 is a view similar to FIG. 5, showing the same fabric in its relaxed condition;

FIG. 7 is a view similar to FIG. 6, showing a modified form of the fabric;

FIG. 8 is a view taken along line 8-8 of FIG. 1;

FIG. 9 is a side diagrammatic view of a needle loom similar to FIG. 1 and showing one step in stitch formation from a first catch cord;

FIG. 10 is a view similar to that of FIG. 9 and showing a second step in the stitch formation;

FIG. 11 is a view similar to that of FIG. 9, showing a step in stitch formation of a second catch cord;

FIG. 12 is a plan view of a modified mechanism for alternately presenting two or more catch cords to a knitting needle;

FIG. 13 is a side elevation looking in the direction of arrow 13, FIG. 12;

FIG. 14 is a longitudinal section view taken on line 14-14 of FIG. 12 showing support for the cams;

FIG. 15 is a perspective view of the catch cord presenting elements of the modified mechanism of FIG. 12 and showing one of the catch cords in active position;

FIG. 16 is a view similar to FIG. 15 but showing the other catch cord in active position;

FIG. 17 is a side elevation of a second modification of a mechanism for alternately presenting two or more catch cords to a knitting needle;

FIG. 18 is a view looking in the direction of arrow 18, FIG. 17; and

FIG. 19 is a view of a prior art knitted selvage formed from one catch cord.

The fabric of the present invention is shown in FIGS. l-4 and is designated by the reference character F. The catch cord lockstitch selvage which binds the weft loops 30 at one edge of the fabric and which forms part of the present invention is designated generally at S.

Lockstitch selvage S is made up of two or more catch cords which are formed into a knitted chain which extends through successive weft loops. FIGS. 14 illustrate one example of a lockstitch selvage made from two catch cords each of which forms alternate knitting loops. As seen in those figures, catch cords 34 and 36 form alternate knitting loops 21 and 23 respectively. Each loop extends through a weft loop 30 in the manner shown in the drawings. Unlike a knitted chain made from a single catch cord, the present lockstitch selvage will not unravel when a broken or free end is pulled. FIG. 19 shows a prior art selvage chain knitted from one catch cord. If the free end 25 is pulled, the first loop 27 will be pulled out of the second loop 29 thus making loop 29 the first loop. Loop 29 will then easily be pulled out of the third loop 31 making loop 31 the first loop. The entire chain will unravel in this manner by continuously pulling end 25.

Lockstitch selvageS shown in FIG. 1 for example will not unravel. Considering the fabricF with the selvage S isolated I from the loom, if catch cord 36 were pulled, loop 23' would be pulled out of loop 21'. Continued pulling of catch cord 36 will not unravel the next loop formed from catch cord 36 designated as loop 23'. The more catch cord 36 is pulled, the smaller it becomes and the tighter it becomes around loop 21' which is made from catch cord 34. Although the example of a locking stitch shown in FIGS. 1-4 is made up of two catch cords which individually form alternate loops, other variations may be made in the number of catch cords and the number of consecutive loops of one catch cord. The importantfactor in a multicatch cord locking stitch is that locking occurs when there is an attempt to unravel a knitting loop which is preceded by a knitting loop ofa different catch cord.

The method of forming the catch cord lockstitch selvage of the present invention, together with one mechanism for carrying out the method is shown in FIGS. 14 and FIG. 8.

Referring again to FIGS. 14 and FIG. 8, a portion of a needle loom, generally indicated by the reference number 20, is shown on an enlarged scale. The portion of the needle loom shown in FIG. 1 includes a right-hand harness guide stand 22 which, together with a left-hand stand (not shown), guidingly supports the harness frames, two ofwhich are shown at 24 and 26. The loom can be equipped with several harness frames for producing a variety of weaving patterns. For every weft insertion there is a reciprocation of some of the harness frames, some moving to the down position and some to the up position. The warps W carried by the harness frames will form a new shed for every insertion. A weft inserting member 28 carrying weft loop 30 enters the open warp shed from one side and through to the other side. To prevent the weft loop 30 from being pulled back through the shed when weft inserting member 28 withdraws to the entering side of the shed, a knitting needle 32 is made to reciprocate in the direction of arrow 33 in timed relation to the weft inserting member 28 by means of a reciprocating support 32'. The knitting needle 32 is timed to pass through weft loop 30 and pick up one ofa pair of catch cords 34 and 36. Needle 32 then pulls a loop of the catch cord, through weft loop 30 and a previous catch cord loop to form the knitted chain S. The means for reciprocating the needle support 32, per se, is old and well-known in the prior art and form no part of the invention as any means which will operate the knitting needle in the described manner will be sufficient. Examples of means for operating the needle in this fashion will be found in US. Letters Pat. Nos. l,604,365 and 3,l02,557, supra.

A reed 40 supported on the usual lay (not shown) beats the weft to the fell of the fabric F after every weft insertion. Catch cords 34 and 36 are selectively raised and lowered by heddles carried by harness frames 24 and 26, respectively, and guided by a U-shaped guide 42 mounted on the lay. An elongated member 44 is mounted centrally of member 42 to separate and prevent entanglement of catch cords 34 and 36. As reed 40 approaches the fell of the fabric F to beat up a weft yarn, guide 42 presents the catch cords to the knitting needle in much the same way as guide 38 as shown in FIGS. 7-10 in the previously mentioned Shackleton application. The only other condition which has to be met in the present application is that the catch cord selected to be picked up by the knitting needle must be brought to the proper height. This is determined by whether the harness frames carrying the catch cords are up or down. If a harness frame is up, the catch cord which it carries will be placed in position to be picked up by the knitting needle as shown in FIGS. 9-l1. In these FIGS. harness frames 24 and 26 are alternately raised and lowered so that each frame presents its respective catch cord to the knitting needle every other weft insertion. In FIG. 9, harness frame 26 is up and catch cord 36 is in position to be picked up by needle 32. FIG. shows a loop 45 ofcatch cord 36 being pulled through weft loop 30 and a previously formed catchcord loop 23 from catch cord 34. FIG. 11 shows needle 32 about to pick up catch cord 34 as it is in the raised position due to the raising of harness frame 24.

FIGS. l-3 match FIGS. 911 respectively with respect to timing and more clearly illustrate the structure of the selvage produced by the operationjust described.

Although a particular sequence of one catch cord up and one catch cord down in alternate sequence is illustrated, other patterns could be used. One catch cord could be up for two or more weft insertions and then the other catch cord could be up for one or more weft insertions; or more than two catch cords could be used in any combination or sequence. It is felt however that the sequence shown with two catch cords, represents the simplest arrangement.

Referring to FIGS. 12l6 there is shown a modified mechanism for selectively presenting a plurality of catch cords to knitting needle 32. Referring more particularly to FIGS. 12

and 13, the usual lay L is mounted for reciprocation on a shaft 48 which is driven from a shaft 50 through equal pulleys 52 and 54 and timing belt 56. Shaft 50 operates weft inserting member 28 and knitting needle 32 through means not shown but well-known in the art. Shaft 50 is in turn driven by a pulley 58 and a timing belt 60 from a motor (not shown). A sleeve 62 is rotatably mounted on shaft 48 on ball bearing 64. Fixedly mounted on sleeve 62 is a pulley 68 and two catch cord control cams 70 and 72. Pulley 68 is driven by' a timing belt 73 from a pulley 74 fixedly mounted on shaft 50. Pulley 74 is onehalf of the diameter of pulley 68'so therefore causes pulley 68 to rotate sleeve 62 at half the speed of shaft 48.

Referring more particularly to FIGS. 15 and 16, a pair of catch cord supporting levers 76 and 78 are pivoted on a pin 80 which is mounted on harness guide stand 22. Levers 76 and 78 have upwardly extending portions 82 and 84 which have guide eyes and 92 respectively through which catch cords 34 and 36 are respectively threaded. A pair of intermediate levers 85 and 86 are pivoted on a pin 87 mounted in a housing 88. Levers 85 and 86 have cam followers 94 and 96 respectively at one end thereof which engage cams 70 and 72 respectively.

The opposite ends of levers 85 and 86 have projecting portions 89 and 91 respectively which engage slotted portions 93 and 95 of levers 76 and 78 respectively. Cams 70 and 72 have high portions 98 and low portions 100. When the follower of an intermediate lever engages the high portion 98 of its respective cam, it causes the intermediate lever to rock around pivot 87 and lift the slotted end of its respective supporting lever. When the slotted end of one of the supporting levers is so lifted, the lever is rocked around pin 80 thereby lowering its upwardly extending portion and the catch cord which it supports. When a cam follower engages the low portions 100 of its respective cam, its corresponding intermediate lever is pivoted so that the corresponding supporting lever raises the catch cord supported thereby. Springs 97 and 99, attached to levers 85 and 86 respectively, maintain cam followers 94 and 96 in engagement with cams 70 and 72, respectively. Cams 70 and 72 are out of phase so that each catch cord will be moved to the raised position to be picked up by the knitting needle every other weft insertion and they will appear in the raised position on alternate weft insertions. The effect will be the same as was produced by the actuation of the catch cords by harness frames 24 and 26 and the selvage produced will be the same as shown in FIGS. 2-4. Variations in the sequence of presenting the catch cords to the knitting needle can be accomplished by varying the drive ratio between pulleys 74 and 68 and changing the configuration of cams 70 and 72. Additional catch cords may be introduced by adding catch cord control cams together with cooperating catch cord supporting levers.

Referring to FIGS. 5-7, there is shown one type of fabric which could be produced by using three catch cords and varying the sequence of presenting them to the knitting needle. The pattern shown in FIG. 5 would be particularly adapted for producing a decorative fringe effect on a stretch fabric which is woven in the stretched condition and which then relaxes to a shrunken condition as soon as it leaves the loom as illustrated in FIG. 6. With a fabric of this type, the bulk of the knitting loops would be formed with two catch cords 102 and 104. A third catch cord 106 is introduced periodically every fifth or seventh loop for example. Since the infrequent use of the third catch cord 106 would create an appreciable gap between loops made from that cord as for example loops 108, I10, 112 and 113 a series of floats 114 would be created. When the fabric is relaxed as shown in FIG. 6, the floats bulge out to produce a fringe effect.

FIG. 7 illustrates a modification of the fabric shown in FIG. 6 wherein a fourth catch cord, 116, is introduced periodically to form knitting loops intermediate the knitting loops formed by catch cord 106 to produce a series of intermediate floats 118. Catch cords of different colors or textures could be used to produce a variety of decorative effects and yet produce a locking stitch of which the fabric in FIGS. 6 and 7 are examples.

indicated at 120. The second modification includes a pair of catch cord presenter rods 122 and 124 which have guide eyes 126 and 128 respectively through which catch cords 34 and 36 are guided. Presenter rods 122 and 124 are reciprocated vertically from their lower ends by a pair of crank members 130 and 132 respectively. Crank members generally indicated at 130 and 132 form part of a shaft 134 which is mounted in bearings 136 and 138, which are fixed to guide stands 22. Rods 122 and 124 are guided in slots 133 and 135 respectively in a bracket 137.

Fixed to an extending portion of shaft 134 is a pulley 140 which is driven by a timing belt 142 from a pulley 144 fixed to shaft 50. The ratio of pulley 140 to pulley 144 is such that shaft 134 makes one revolution for every two revolutions of shaft 52. Since shaft 50 makes one revolution for each weft insertion, shaft 134 will make one revolution for every two weft insertionsuEach presenter rod will therefore be raised and lowered once for every two weft insertions. Crank means 130 and 132 are 180 out of phase. with respect to pulley 140 so that presenterrods 122 and 124 will be raised on alternate weft insertions. When a presenter rod is brought into a raised position, the catch cord being guided thereby is raised into a position where it will be picked up by the knitting needle as in the case of the previously described embodiments of catch cord presenter mechanisms. If it is desired to use more than two catch cords, the ratios of pulleys 140 can be varied so that shaft 134 will make one revolution for as many weft insertions as there are crank driven presenter rods. Additional shafts and crank driven presenter rods could be added or cams could be substituted for cranks as means to lift the presenter rods.

As will be evident from the foregoing description, certain aspects of the invention are -not limited to the particular details of construction or the examples illustrated and it is contemplated that other modifications skilled in the art.

lclaim: 1. A woven fabric comprising: a. a plurality of warp yarns; I b. a plurality of loops of weft yarns interwoven with said warp yarns and terminating in closed loops at one edge of said fabric; and i e selvage means for securing each of said loops to adjacent loops, including a chain of knitted loops formed from a plurality of interknitted catch cords, wherein a portion of one catch cord passesthrough a weft loop and a portion of another catch cord passes through an adjacent weft loop whereby-said closed loops are secured to each other solely by said knitted catch cords. 2. A woven fabric as described in claim 1 wherein the loops of said chain are formed of a'pair of catch cords.

3. A woven fabric as described in claim 1 wherein adjacent loops of said chain are formed of different catch cords.

4. A woven fabric as described in claim 3 wherein the loops of said chain are formed of a pair of catch cords.

5. A woven fabric as described in claim 1 wherein saidloops formed of one of said catch cords in said chain are separated by more than one loop of said differing catch cords.

6. A woven fabric as described in claim 5 wherein said warp yarns are elastic and said one catch cord forms a picot float between its knitted loops.

7. In the manufacture of a woven fabric in which loops of weft are inserted into successive warp sheds, a method of binding in such loops 'of weft to form a knitted lockstitch selvage at the edge of the fabric opposite the edge at which said weft insertions are made, which method comprises the steps of:

a. inserting first and second weft loops into first and second warp sheds;

b. pulling a first knitting loop from a first catch cord through said first weft loop before said second weft loop is inserted into said second warp shed; and

will occur to those c. pulling a second knitting loop from a second catch cord through said second weft loop and said first knitting loop before a subsequent :weft loop is inserted into a subsequent warp shed whereby a chain of knitting loops, portions of which extend through said weft loops, is formed to bind said weft loops in said fabric.

8. The method as set forth in claim 7 wherein said first and second knitting loops are formed alternately throughout said chain.

9. The method set forth in claim 7 comprising the additional step of pulling a loop from a third catch cord through a third weft loop and said second knitting loop to form a third knitting loop.

10. The method set forth in claim 7 wherein a plurality of loops are formed from said second catch cord between the formation of loops from said first catch cord.

11. The method set forth in claim 7'comprising the additional step of pulling still another loop from a catch cord other than said first catch cord through a third weft loop and said second knitting loop to form a third knitting loop, whereby loops in said chain'of knitted loops formed from said first catch cord are separated by more than one loop formed from cords other than said first catch cord.

12 In the manufacture of a woven fabric in which loops of weft are inserted by a weft inserting member into successive sheds of warp yarns, a method of binding in such loops of weft to form a knitted lockstitch selvage at the edge of the fabric opposite the edge at which said weft insertions are made, which method comprises the steps of:

a. inserting a first weft loop into a first warp shed;

b. moving a knitting needle through said first weft loop;

0. presenting a first catch cord to said knitting needle;

d. drawing a first knittedv loop from said first catch cord through said first weft loop;

e. subsequently inserting a secondweft loop into a second warp shed;

f. moving said knitting needle through said second weft loop; I,

g. presenting a second catch cord to said knitting needle;

and i h. pulling a second knitting loop from said second catch cord through said second weft loop and said first knitting loop whereby a chain of knitting loops are formed from said catch cords, each of said catch cords having portions which extend through said weft loops to bind said weft loops in said fabric.

13. The method as set forth in claim 12 comprising the additional step of presenting a-third catch cord to said knitting needle when it is in its rearward position of a third reciprocation so that said third catch cord will be pulled through a third weft loop and said second knitting loop to form a third knitting loop when said needle moves to its forward position.

14. in the manufacture of an elastic fabric in which loops of weft are inserted by a weft inserting member into successive sheds of elastic warp yarns under tension, a method of producing a decorative fringe at the edge of the fabric opposite the edge from which said weft insertions are made which method comprises the steps of:

a. reciprocating a knitting needle through successive weft loops between a forward and a rearward position at said opposite edge; a

b. presenting a first catch cord to said knitting needle when it is in the rearward position of a first reciprocation so that said first catch cord will be pulled through a first loop to form a first knitting loop when said needle moves to said forward position;

c. selectively presenting other catch cords individually to said knitting needle when it is in the rearward position for several successive reciprocations of said needle to form a chain of knitted loops within successive weft loops beginning with said first knitting loop; and

d. presenting said first catch cord to said knitting needle when it is in the rearward position so that it will be pulled through a subsequent weft loop and the last formed loop of said chain of knitted loops, whereby the portion of said first catch cord which floats between points where it is formed into a knitted loop will produce a decorative fringe.

15. In a loom for weaving fabric, in which successive loops of weft are inserted in successive warp sheds from one side of said fabric by a weft inserting member, lockstitch knitted selvage forming means at the other side of said fabric, comprising:

a. a hooked latch knitting needle adapted to reciprocate through said weft loops;

b. means to reciprocate said latch knitting needle in timed relation with said weft inserting member so as to penetrate said weft loops whereby the weft loops are laid below the latch of said needle; and

. means to selectively present one of a plurality of catch cords to said knitting needle when the hook of said needle has fully penetrated each of said weft loops, said presenting means comprising a means spaced from the edge of said fabric for selectively guiding said catch cords into contact with said needle whereby a chain of knitted loops are formed from said plurality of catch cords.

16. The selvage forming means as set forth in claim 15 wherein said presenting means alternately present a pair of catch cords, one at a time, to said knitting needle.

17. The selvage forming means as set forth in claim 15 wherein said presenting means comprise guides on harness frames which reciprocate to bring said catch cords into and out of engagement with said knitting needle.

18. The selvage forming means as described in claim 15 wherein said presenting means comprise:

a. movable lever means, each having a catch cord guiding eye at one end and cam follower at the other end; and

b. cams for engaging said followers and moving said lever means to selectively bring said catch cords into and out of engagement with said knitting needle.

19. The selvage forming means as set forth in claim 15 wherein said presenting means comprise: 1 i i a. a presenter for each catch cord comprising a lever having a guide eye for said catch cord on one end; and

b. crank means connected to the other ends of said lever to selectively raise and lower said catch cords to bring them into engagement with said knitting needle.

20 In a loom in which successive loops of weft are inserted in successive warp sheds from one side of said fabric by a weft inserting member, selvage forming means at the other side of said fabric, comprising:

a. a hooked knitting needle adapted to penetrate said weft loops;

b. means to reciprocate said knitting needle in timed relation with said weft inserting member so as to penetrate said weft loops; and

0. means spaced from the edge of said fabric for selectively presenting a catch cord to said knitting needle when the hook of said needle has fully penetrated said weft loops to draw loops of said catch cordthrough selected weft loops, some of which are spaced at least two weft loops apart.

21. The selvage forming means as set forth in claim 20 wherein said presenting means is a catch cord guide mounted on a harness frame.

22. The selvage forming means as described in claim 20 wherein said presenting means comprise:

a. a lever movable to and from catch cord presenting position, said lever having a'guide eye at one end and a cam follower at the other end; and

b. a cam for engagingsaid follower for selectively moving said lever into catch cord engaging position. 

